This is a proposal to 1) provide training leading to the M.S. and Ph.D. degrees in intervention and evaluation strategies to reduce the incidence of new drug users and the transmission of HIV among them and to others; 2) to provide in-country training in (a) strategies to reduce new drug users, continued drug use, and transmission of HIV among drug users, and (b) the ethics of research and intervention programs to researchers and health professionals responsible for combating drug use and the HIV epidemic, and 3) to collaboratively develop, implement, and evaluate a community intervention program in a commune in Quang Ninh Province, the province with one of the highest rates of drug use and the highest rate of HIV in Vietnam. Although drug use and HIV transmission has continued for the last decade in southern Vietnam, primarily among older drug users, and explosive epidemic of both drug use among young men and HIV infection among drug users has occurred within the last three years in northern Vietnam. This recent epidemic has spread rapidly to other groups; the prevalence of HIV among military recruits and STD clinic attenders is now 4 percent and among antenatal clinic attenders is 2 percent in Quang Ninh Province where we propose to develop, implement, and evaluate a collaborative community intervention program. Two communes will be selected for the evaluation of the community intervention program which are matched for the prevalence of drug use among young men, of injecting drug users, and of HIV, and the proportion of minority youth. The communes will be selected in geographically separate areas to assure that diffusion of the intervention to the control commune is minimized. One will be randomly assigned to the intervention program. Surveys for the number of drug users reporting initiation of drug use in the past year, and prevalence of drug users, injectors, and sharers, and HIV will be conducted before implementation of the intervention and two years later. The success of the intervention will be determined by comparing the difference in the proportion of young men reporting initiation of drug use, injecting and testing positive for HIV in the previous year at the base-line and follow-up surveys.